Musculoskeletal conditions in children attending two Togolese hospitals.

OBJECTIVE: A retrospective study was conducted in order to point out the different kinds of musculoskeletal conditions observed in children attending two Togolese hospitals. RESULTS: A total of 434 (242 females, 192 males) of the 29 620 children examined (1.5%) were suffering from these conditions. Probable joint and bone infections (187 patients, 43%), limb deformities (106 patients, 24%), osteochondrosis (60 patients, 14%) and vaso-occlusive crisis due to haemoglobinopathies (29 patients, 7%) were the main conditions observed. Osteomyelitis observed in 128 patients affected the humerus (25 patients), radius (10 patients), femur (68 patients), tibia (15 patients), fibula (five patients), and both tibia and fibula (five patients). Probably, infectious arthritis seen in 30 patients affected mainly the hip (11 patients) and the knee (13 patients). In the spine, infection affected the midthoracic and upper lumbar areas. Underdevelopment, sickle cell anaemia and sickle cell haemoglobin C disease were the main risk factors in determining susceptibility to infections. Vaso-occlusive crises were due to sickle cell anaemia (11 patients) and sickle cell haemoglobin C disease (18 patients). Osteochondrosis seen in 60 patients free from haemoglobinopathy involved the spine (Scheuermann's disease, 38 patients) and the hip (Legg-Calvé-Perthes disease, 22 patients). Limb deformities were observed in the knee (varus and valgus deformities in 64 patients) and the foot (talipes varus equin in 40 patients). CONCLUSION: This study's findings, which require further confirmation, suggest some conclusions. Scheuermann's disease can explain in part the degenerative disc conditions observed in African adults. Valgus and varus deformities play an important role in the development of knee osteoarthritis in Black Africa. An African child with joint or bone pain should be investigated for sickle cell anaemia. In the future, improved lifestyle and better health care will be essential to reduce bone and joint infections, and allow refined diagnosis of connective tissue diseases now probably underestimated in African children.

Images of truncated one-dimensional periodic bar targets in aberration-limited optical systems.

This paper deals with the properties of the images of truncated one-dimensional periodic bar targets formed by aberration-limited optical systems. Attention is directed to the problem of determining how many bars are required at a given spatial frequency in order to obtain an image which closely approximates that for an infinite-chain periodic bar target. Numerical calculations are carried out for the case of an aberration-limited, glancing-incidence x-ray telescope.